System of control.



. No. 809,774. PATENTED JAN. 9, 1906.

F. E. CASE.

SYSTEM OF CONTROL.

APPLICATION FILED JUNE 12,1905.

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Wirnesses. lnvenror. f/LL Frank E.CG6 a: Z 4 2/ WWW 1- MW UNITED STATES PATENT oEEIoE.

FRANK E. CASE, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEIV YORK.

SYSTEM OF CONTROL.

Specification of Letters Patent;

Patented Jan. 9, 1906.

Application filec ulle 12, 1905. Serial No. 264,763.

11 1/7/71 'Lli7b07771 it may concern.-

Be it known that I, FRANK E. CAsE, a citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Systems of Control, of which the following is a specification.

The present invention relates to control apparatus for electric motors which, as in a case of railway-motors, are controlled from a remote point.

In systems wherein a number of motors are not connected together permanently in a closed circuit and the motors are series Wound some means must be provided for connecting the motors in one or more closed circuits and for reversing the armature connections relatively to the series field in case it is desired to cause the motors to operate as braking generators. For this purpose it should be possible to operate the reversingswitch without also operating the controller to complete the connections between the motors and the source of current-supply. Moreover, in case the current-supply fails it should still be possible to operate the reversingswitch.

In one of its aspects the present invention consists in motor-control apparatus comprising a motor-controller of the separately-actuated contact type and a reversing-switch so arranged that the controller in its normal. or off posit-ion completes a circuit containing the motor or motors together with means for operating the reversing-switch independently of the current from the source of supply.

In another of its aspects the present invention comprises a motor-controller of the sepa rately-actuated contact type arranged to be operated by current from the main source of current-supply and to assume a position wherein a local motor-circuit is completed upon failure of current, together with a re versing-switch and pneumatic or other locally-supplied power for operating the reversing-switch.

In my application Serial No. 226,755 I have disclosed a control system comprising a motor-controller of the separately-actuated contact type, some of the contacts of which are adapted to close in automatic progression, a reversing-switch controlling circuits for the controller and reversing-switch, and a pneumatic system for controlling the said circuits. In this system there is also provided a circuit-breaker which is closed and held closed by a pneumatic pressure. lNhere the circuit-breaker is closed and held closed entirely by the pressure in the pneumatic system, it is evident that when the motorman stops the car from time to time the circuit-breaker is continually opened and closed and quite unnecessarily, since it is sufficient if the circuit-breaker opens only upon overload and upon failure of the motor-circuit to open when the pneumatic system is exhausted.

In another of its aspects the present invention consists in an improved arrangement of circuit-breakers whereby in a control system of the character disclosed in my aforesaid application the circuit-breaker does not open Whenever the pneumatic system is exhausted,

but only upon overload and in case the motor-circuit is not broken when the pneumatic system is exhausted.

The present invention further consists in a novel operating means for the reversingswitch and interlocks between the reversingswitch and the motor-controller, whereby the pressure in the pneumatic system must always be greater than that required to operate the reversingeswitch in order that the actuating means for the motor-controller contacts may be energized. 4

The present invention in the above and other of its aspects will be more fully understood by reference to the following descrip tion thereof.

In the accompanying drawings, Figure 1 indicates diagrammatically the motor and control equipment of a single car arranged in accordance with the present invention, and Fig. 2 illustrates the normal condition of the motor-circuit when the controller is deenergized.

Reference being had to the drawings, M and M represent two series motors.

T is a source of current-supply, such as a trolley or a sliding contactshoe.

R R are resistance-sections adapted to be inserted in the motor-circuits and removed therefrom in order to accelerate the motors.

GB is a circuit-breaker. BS is a reversing-switch which changes the relative connections of the armature and field windings.

C is a motor-controller of the separatelyactuated contact type.

O is a combined throttle and time-limit relay for regulating the automatic progression of the resistance-controlling contacts.

The motor-controller C, together with the throttle-relay, maybe and as illustrated are identical in every respect with the controller and relay illustrated and described in my aforesaid application, except that in addition to the usual line-switches or contacts designated by the characters T T, &c., two additional switches or contacts T T are provided. These two latter switches instead of being normally open are normally closed, thereby serving to connect two terminals of the motors together and the other two terminals to ground. The series switch S, the parallel switches P and P, the bridging-switch B, and the resistance switches R to R are the same in each case.

The circuit-breaker may be of any desired type, but is preferably similar to that shown in my application Serial No. 227,812, to which application reference may be had for a detailed description. In that circuit breaker two coils, one in electric controllingcircuit and the other in the motor-circuit, act upon a common armature in such a manner that when both coils are simultaneously energized or deenergized the armature moves without producing any effect. Should, how ever, the controlling-circuit be interrupted, deenergizing one of the coils and should at the same time the motor-circuit remain closed, maintaining the other coil energized, the armature will swing about a pivot and trip the circuit-breaker. According to my present invention 1 substitute for the coil in the controlling-circuit a piston in the pneumatic system, so that in case the pressure is exhausted without producing an interruption of the motor-circuit the circuit-breaker is tripped.

Briefly stated, the circuit-breaker com prises a contact-arm 50, connected to the core of an actuating-electromagnet 52. The circuit-breaker is set when the electromagnet 52 is energized and is held closed by a suitable catch 56, which engages a projection on one arm of the toggle 58. The toggle 58 is not moved into a straight line when the arm 50 is in its closed position, so that when otherwise free the arm opens automatically. The circuit through the closing or setting coil is completed at a switch 61, normally held open by means of a spring 62 and preferably lo cated within easy reach of the motorman.

The setting-circuit passes through an auxiliary switch 2, connected with one of the line switches or contacts, as T and which is closed only when the line-switch is open.

65 The circuit-breaker tripping means consists of a lever 64, pivotally arranged adjacent the catch 56 and normally out of engagement with said catch. This lever constitutes an armature of an electromagnet 66, located in the motor-circuit. hen the motor-current exceeds a safe maximum, the lever 64 is attracted and strikes against the catch 56, thereby tripping the circuit-ln'eaker.

69 is a second tripping-lever, illustrated as arranged adjacent the lever 64, although it is of course evident that it could be made to operate directly uponthe catch 56. One end of the lever 69 is connected to a double set of pistons and 71, while at an intermediate point it is pivotally connected to the core of electromagnet 68, the coil of which is energized by motor-current.

7 2 and 7 3 are springs against the tension of which the pistons and electromagnet 68 move the lever.

It will be seen that when electromagnet 68 and the pistons are energized or deenergized simultaneously the lever 69 has a rectilinear movement; but should the air be exhausted from the pistons, causing them to assume the position shown, while the electromagnet 68 remained energized, the lever 69 will be given a rotary movement about its pivotal connection with the electromagnet 68, striking the lever 64 and tripping the circuit-lneaker.

The circuits for energizing the actuating means for the motor-controller all pass through switches D and D, associated with the reversing-switch, and through a group of switches E and another group of switches F. The reversing-switch is moved in one direc tion or the other by means of pistons 1' 1", and the switches E and F are controlled, respectively, by pairs of pistons e e andff. As in the previous system, two train-pipes 1. and 2 are employed, each being connected to one piston at each set of pistons, the direction of rotation of the motors being determined by the order in which the pipes are energized. Air is admitted to these pipes from a reservoir A through pipe 3 and one of the motor mans valves V and V.

The pistons 1" and r are connected to the reversing-switch through the medium of springs r and r, the tension of which is such that when the pressure applied to either of pistons is only sufficient to operate the re versing-switch the corres )onding spring is not compressed sufliciently to close the auxiliary switches D or D, as the case maybe, it being necessary in order to close either of these switches to supply air at a greater pressure than that required to simply throw the reversing-switch. The purpose of this is to cause the motor-controller to come to its off position as soon as the pressure in the pipe, which determines the direction of rotation of themotors, decreases to a point slightly above that at which the reversing-switch will operate and since, as will hereinafter appear, the

pressure in the pipe which is the last to be energized is never suflicient to close the auxiliary switches, even if the reversing-switch should be operated, it is impossible to accidentally reverse the motors while connected across the line when air is admitted to the second pipe in order to change the motor connections from series to parallel.

Aside from the auxiliary switches D and D the controlling-circuits are in the main the same as in my prior application, Serial N 0. 226,755. hen either of switches D or D is closed, a circuit is completed through the actuating-coils of contacts T, T and T T and T, and when, in addition, either of switches e e of the group of switches E is closed the actuating-circuit for the series contact 8 is completed. In order to accelerate, switches f 2 or f 3 of the group F must be closed, and in order to connect the motors in parallel both switches e and 6 must be closed at the same time.

Assuming that the direction of rotation is to be determined by pipe 1, air is first ad mitted to this pipe at a low pressure, which may be assumed to be ten pounds. Piston 71 is thereupon forced upwardly, piston e is act uated, closing switches e and c and piston r is moved'sufliciently to throw the reversingswitch to the position indicated, but not sufiiciently to close the switch D. When the pressure in pipe 1 is raised to twenty pounds, the switch D is closed, completing the actuating-circuit through the linecontacts,whereby contacts T, T and T are closed and contacts T T are opened. Since the switch e has been previously closed, the actuating circuit for the series contacts is now also completed and the series contact closes, connecting the motors across the line in series with each other and with all the resistance in circuit, provided that the circuit-breaker if open was set before line-contact T closed. In order to accelerate the motors, pressure in pipe 1 is raised thirty pounds, causing piston f to be actuated, closing switch The closing of this latter switch completes the ac tuating-circuit for the resistance-contacts and causes them to be closed in automatic succession until all the resistance is elimi nated. When it is desired to connect the motors in parallel, the pressure in pipe 1 is reduced to twenty pounds, enabling the resistance-controlling contacts to open, and air is admitted to the pipe 2 to the pressure of ten pounds, actuating piston c and closing switch 6 Since switches e and c are both closed, the actuating-circuit for the parallel contacts is completed and the parallel contacts P and P are closed, connecting the motors across the line parallel with each other and with all resistance in circuit. Upon raising the pressure in pipe 1 to thirty pounds again, switch f is closed and the resistancecontacts will again close in automatic progression, as before, until finally the motors are left connected acrossthe line in parallel with no extraneous resistance in circuit. For

operating the motors in the reverse direction air must be admitted to the pipe 2 first, and it is this pipe which will be supplied with air at ten, twenty, and thirty pounds pressure, while the pressure in pipe 1 will never be allowed to rise above ten pounds.

The motormans valve, whereby the pressure in the two pipes is determined, is illustrated as consisting of plug-valve o and diskvalve 4), the plug-valve having ports 4 and 5 and other ports 6 and 7. In the position shown the port 6 connects pipe 1 to passage 11 in the main-valve casing, and port 7 connects pipe 2 to another passage 10. By turning the plug-valve pipe 1 may be connected to passage 10 through port 4 and pipe 2 to passage 11 through port 5, thereby reversing the conditions which will be produced in the pipes upon operating the disk valve 0;. In the position shown both pipes are exhausted through ports 18 and 19 in the disk valve, these ports connecting with atmosphere. The pipe 3, leading from reservoir A, is connected to a central chamber 12 in the disk valve, and from this chamber extend radial ports 13, 14, 15, 16, and 17, each of which is provided with a reducing-valve. When the valve is turned to its first position, air passes from chamber 12 through port 13 into pipe 1 at a pressure of ten pounds. In the next position of the valve pipe 1 is supplied with air at twenty-pounds pressure through port 14 and in the following position, with air at thirty-pounds pressure through port 15. The port 20 is provided with a reducing-valve, which permits the air in pipe 1 to exhaust to atmosphere until it has been reduced to a pressure of twenty pounds. When port 17 comes in front of the passage 10, air is admitted to pipe 2 at ten-pounds pressure, and finally when port 16 registers with passage 11 the pressure in pipe 1 is again raised to thirty pounds. The mechanical construction of the motormans valve may be the same as that in my prior application.

Although I have illustrated the present in-- vention in its preferred form, I do not desire to limit it to the particular form shown, since many changes in the construction and organization of the parts may be made and certain features may be used either in connection with or separate from other features illustrated without departing from the present invention.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In a system of control, in combination, a motor-circuit, a pneumatic controlling system, a circuit-breaker in said motor-circuit,

and means operable upon the exhaustion of said pneumatic controlling system while the motor-circuit remains energized to trip said circuit-breaker.

2. In a system of control, in combination, a motor-circuit, a pneumatic controlling system, a circuit-breaker in said motor-circuit, and means operable upon the exhaustion of said pneumatic system for tripping the circuit-breaker when the motor-circuit remains energized but not when the motor-circuit is denergized.

3. In a system of motor control, in combination, a motor-circuit, a pneumatic controlling system, a circuit-breaker, means for setting said circuit-breaker, means for tripping said circuitbreaker on overload in the motorcircuit, and means for tripping the circuitbreaker uponthe exhaustion of the pneumatic controlling system while the motorcircuit remains energized.

4. In a system of control, in combination, a motor-circuit, a pneumatic controlling system, a circuit-breaker, a piston in said pneumatic system, an electromagnet in said motor-circuit, and means cooperating with said piston and said electromagnet for tripping the circuit-breaker upon the exhaustion of the air from said piston while said electromagnet remains energized.

5. In a system of control, a motor-circuit, a pneumatic controlling system, a circuitbreaker, a piston in said pneumatic system, an electromagnet in said motor-circuit, and means cooperating with said piston and said electromagnet for tripping said circuitbreaker upon the exhaustion of air from said piston while the said electromagnet remains energized, the arrangement being such that the circuit-breaker is not tripped when the exhaustion of the piston and the deenergization of the electromagnet take place simultaneously.

6. In a system of control, a motor, a controller arranged to connect said motor to a source of current-supply, electromagnetic actuating means therefor, a reversing-switch, actuating means for said reversing-switch, and means associated with the actuating means for the reversing-switch for completing a circuit through the controller-actuating means after the reversing-switch has been fully operated.

7. In a system of control, a motor, a controller arranged to connect said motor to a source of current-supply, actuating means for said controller, a reversing-switch, a piston for actuating said reversing-switch, a yielding connection between said piston and said reversing-switch, and means associated with said piston for controlling the energizing-circuit of the controller-actuating means.

8. In a system of control, a motor, a controller arranged to connect said motor to a source of current-supply, actuating means for said controller, a reversing-switch, a pistroller-contacts.

ton for actuating said switch, a yielding connection between said piston and said switch, and contacts associated with said piston for controlling the energizing-circuit ofsaid controller-actuating means, the said yielding connection being arranged to maintain said contacts open except when the pressure upon the piston is greater than that required to operate the reversing-switch.

9. In a system of control, a motor, a controller for connecting said motor to a source of current-supply, electromagnetic actuating means for said controller, a controlling-circuit for said actuating means, a reversingswitch, a pneumatically-actuated piston, a spring between said piston and said switch, and contacts associated with said piston and arranged in said controlling-circuit.

10. In a system of control, a motor, a controller for connecting said motor to a source of current-supply, electromagnetic actuating means for said controller, a controlling-circuit for said actuating means, a reversingswitch,. a pneumatically-actuated piston, a spring between said piston and said switch, and contacts associated with said piston and located in said controlling-circuit, the tension of the spring being such that said contacts are closed only upon a greater pressure than that required to operate said reversingswitch.

11. In a system of control, a plurality of motors, a motor-controller arranged to connect said motors to a source of current-supply in series with each other and to connect them in a closed circuit when the controller is in its off position, means controlled by current from said source of supply for operating said controller, a reversing-switch for said motors, and means independent of the current from said source of supply for operating said reversing-switch.

12. In a system of control, a plurality of motors, a controller having normally closed contacts for connecting said motors in a closed circuit and normally open contacts arranged to connect the motors to a source of current-supply, electromagnetic actuating means for said contacts, means for connecting said actuating means to said source of supply, a reversing-switch, and independent means for operating said switch.

13. In a system of control, a plurality of motors, a motor-controller comprising a plurality of contacts for connecting said motors to a source of current-supply, and normally closed contacts for connecting said motors in a closed circuit, electromagnetic controlling means for said contacts, an actuatingcircuit for said controlling means arranged to cause said normally closed switches to open when others of said switches are closed, a reversing-switch, and means for operating said. reversing-switch without operating the con.-

IIC

14. In a system of control, a plurality of motors, a motor-controller including nor mally closed contacts arranged to connect said motor in a closed circuit, a source of current-supply, means controlled by current from said source of supply for operating the controller and opening said contacts, a reversing-switch, and means independent of said current for operating said switch.

15. In a system of control, a plurality of motors, a motor-controller arranged to connect said motors to a source of current-supply and including normally closed contacts arranged to connect said motors in a closed circuit, means controlled by current from said source of supply for operating said controller and opening said contacts, a reversing-switch, and means independent of the current furnished by said source of supply for operating said reversingswitch.

16. In a system of control, a plurality of motors, a motor-controller adapted to return to its off position when otherwise free and arranged to connect said motors in a closed circuit when in its ofl' position and to connect them to a source of current-supply in series with each other when in a running position, means controlled by current from said source of supply for maintaining said controller in a running position, a reversing-switch, and means for operating said reversing-switch independently of said current.

17. In a system of control, a plurality of motors, a motor-controller of the separatelyactuated contact type arranged to connect said motors in closed circuit when the controller is in its off position, a reversingswitch, electromagnetic actuating means for said controller-contacts, controlling-relays for said actuating means, and pneumaticallyactuated means for operating said relays and said reversing-switch.

18. In a system of control, a plurality of motors, a controller having normally closed contacts for connecting said motors in a closed circuit and normally open contacts for connecting said motors to a source of current-supply, electromagnetic actuating means for said contacts, a governing system independent of the current from said source of supply for connecting said contact-actuating means to said source of supply, a reversing-switch, and means connected with said governing system for operating said reversing switcl1.

In witness whereof I have hereunto set my hand this 9th day of June, 1905.

i FRANK E. CASE.

Witnesses: I

BENJAMIN B. HULL, HELEN ORFORD. 

